The most important applied structure is called Fundamental (Technical) Plans (FP). The plans can indeed also reach beyond pure technique, such as organization. The main author has worked within this area as a consultant and as a teacher for many years, starting in the 1970s. The students have represented operators from all over the world. Historically, after a long stable period during the twentieth century, digitization brought the need for a synchronization plan in addition to a basic set of plans. The area of IN and mobility were the next challenges to the basic ‘FP house design’. A main contribution was a mobility management plan. Then IP entered the overall telecom area, giving a new touch to the quality of service plan, urging for a separate security plan and for a controllable convergence. The FP view supports no doubt an orderly convergence between technologies. After all, all technologies have a common target: to connect communicating parties in a satisfactory way, technically and economically.